Here is one way you can do it.
Actionscript Code:
stage.addEventListener(Event.ENTER_FRAME, ef);
var ended:Boolean = false;
function ef(e:Event):void{
if(mc.currentFrame == mc.totalFrames){
ended = true;
delay();
}else if(ended && mc.currentFrame == 1){
ended = false;
delay();
}
if(ended){
mc.gotoAndStop(mc.currentFrame-1);
}else{
mc.gotoAndStop(mc.currentFrame+1);
}
}
function delay():void{
stage.removeEventListener(Event.ENTER_FRAME, ef);
setTimeout(function(){
stage.addEventListener(Event.ENTER_FRAME, ef);
}, 1000);
}